479
FXUS65 KFGZ 290508
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1008 PM MST Tue Jul 28 2026

.SYNOPSIS...This morning`s disturbance is continuing to produce
extensive cloud cover, along with showers and thunderstorms across
the central portion of northern AZ, while skies remained mostly
clear over northern and eastern portions of Arizona, allowing new
showers and thunderstorms to develop ahead and east of the
disturbance this afternoon. Chances for afternoon and evening
showers and thunderstorms will continue Wednesday, mainly for the
higher terrain, before temperatures start rising Thursday and
remaining elevated this weekend as the monsoon activity decreases.

&&

.DISCUSSION...Visible satellite and radar imagery shows the center
of the MCV is passing west of Flagstaff, near Williams, and moving
in a north- northwest direction, producing a quick burst of showers
and thunderstorms, and then leaving behind a layer of mid- to upper-
level cloud cover. This cloud layer is helping to suppress new
convection across Prescott, Sedona, Flagstaff, and surrounding areas
this afternoon. However, areas that have remain mostly clear this
morning, especially areas north to northwest of Flagstaff, near the
Grand Canyon, and eastern portions of the CWA, including most of
Navajo and Apache counties, are starting to see new showers and
thunderstorms develop near higher terrain and where daytime heating
was the greatest today. This activity is expected to continue through
the rest of the afternoon and early evening hours before settling
down tonight.

For Wednesday onward, the high pressure that was over New Mexico
will strengthen and shift westward and over Arizona, leading to
an overall decrease in showers and thunderstorms as subsidence
increases and drier, mid-level air moves into the region.
However, this will not completely stop the low-level monsoonal
moisture, so isolated to low-end scattered showers and
thunderstorms will still be possible over the higher terrain
during the late morning and afternoon hours. The decrease in
Monsoon, along with the strengthening and relocation of the area
of high pressure, will cause temperatures to rise above normal by
Thursday, with a more significant rise for Friday through Sunday.
An Extreme Heat Warning for the Grand Canyon (below 4000 ft) will
start at 10 MST Thursday, with additional warnings starting 10
MST/ 11 AM MDT Friday for Yavapai County and northern Gila County
(both below 4000 ft), Marble and Glen Canyon, including the city of
Page, and Oak Creek and Sycamore Canyons, including the city of
Sedona.

&&

.AVIATION...Wednesday 29/06Z through Thursday 30/06Z...ISO-SCT
SHRA/TSRA from 19Z to 03Z, mainly north of a KCMR-KJTC line. Brief
periods of MVFR conditions and gusty outflow winds in excess of 40
kts possible in and around TS. Otherwise, expect VFR conditions with
VRB winds 5-10 kts.

OUTLOOK...Thursday 30/06Z through Saturday 01/06Z...Mainly VFR
conditions. ISO SHRA/TSRA each afternoon/evening, with the greatest
likelihood over the higher terrain. Brief periods of MVFR conditions
and gusty outflow winds possible in and around TS. Otherwise, expect
VRB winds 5-10 kts.

&&

.FIRE WEATHER...Rest of Today through Thursday...Active monsoonal
conditions are expected through the rest of today, with a slow
downturn through Thursday, with isolated to scattered showers and
thunderstorms mainly over the higher terrain. Expect mainly light
winds outside of thunderstorms, but trending toward westerly through
southwest 5 to 15 mph over higher terrain. Daytime temperatures rise
to above normal by Thursday.

Friday through Sunday...A continued downturn in Monsoonal activity
is expected through this period, although isolated showers and
thunderstorms remain possible over higher terrain. Temperatures will
rise significantly during this period, with many areas seeing the
warmest conditions so far this year. Winds will be generally light
and variable, at 5 to 15 mph.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning from 10 AM MST /11 AM MDT/ Friday to 8 PM
MST /9 PM MDT/ Sunday for AZZ005-018-037-038.

Extreme Heat Warning from 10 AM Thursday to 8 PM MST Sunday for
AZZ006.

&&

$$

PUBLIC...Schank
AVIATION...Humphreys
FIRE WEATHER...Schank

For Northern Arizona weather information visit
weather.gov/flagstaff